Method and means for felting fibrous elements



Nov. 20, 1956 R. D. LAMBERT 2,770,844

METHOD AND MEANS 50R FELTING FIBROUS ELEMENTS Filed July 29, 1953 IN VEN TOR.

ATTORNEYS.

nited States Patent 6 METHOD AND MEANS FOR FELTING FIBROUS ELEMENTSRobert D. Lambert, Sandpoint, Idaho, assignor, by mesne assignments, toChangewood Corporation, Chicago, IlL, a corporation of IllinoisApplication July 29, 1953, Serial No. 371,055

13 Claims. (Cl. 19-155) This invention relates to the manufacture ofstnlctures molded of fibrous elements of small to substantial dimensionsuch as up to about inches in length or width and it relates moreparticularly to a method and apparatus for feeding fibrous elements ofthe type described to form a layer of predetermined thickness anddistribution for molding into various objects, such as panel-s andboards, as by means of heat or pressure.

To the present, satisfactory means have not been available for handlingfibrous elements :of such large dimension and for feeding such fibrouselements and automatically depositing them in continuous fashion acrossa surface to form a layer of desired thickness and distribution and itis an object of this invention to provide a method and apparatus foraccomplishing same.

More specifically, it is an object of this invent-ion to provide amethod and apparatus for handling fibrous elements, such as straw-likematerials and woody wafers up to about 5 inches in length, in which thefibrous elements are fed continuously at a uniform rate and distributedfor deposition uniformly across a collecting surface to form a fibrouslayer, in which the fibrous elements are deposited onto the surface in amanner to achieve an interfe'lted relation effective to produce a strongand well integrated structure upon molding, in which deposition isachieved in a manner to lay the fibrous elements onto the collectingsurface without disturbing adjacent elements or elements previouslydeposited thereon, and in which fibrous elements are continuouslydeposited in uniform distribution upon a collecting surface moving at aconstant and uniform rate in one direction to deposit the fibrouselements as an endless layer of uniform thickness, and which handles thefibrous elements in a manner to avoid fracture or disintegration thereofduring processing.

A further object is to provide apparatus for use in a method of the typedescribed which is formed of relatively few simple parts and is simpleand expedient in operation and control for the uniform deposition offibrous elements across the width of a collecting surface, and it is arelated object to produce apparatus 'of'the type described which avoidsthe use of small metering orifices which might become plugged eitherwith an abnormally long fibrous element or with adventitious objects tointerfere with the normal operation of the device. v

These and other objects and advantages of this invention willhereinafter appear, and for purposes of illustration, but not oflimitation, embodiments of the invention are shown in the accompanyingdrawing in which:

Figure '1 is a side elevational view of one form of apparatus embodyingfeatures of this invention;

Figure 2 is a top plan view taken substantially along the line 22 ofFigure '1;

Figure 3 is an enlarged fragmentary view of a portion of the apparatusshown in Figure 1;

"Figure 4 is a schematic view of a modification which may be made in thelower portion of the apparatus shown in Figure l, and

Figure 5 is a front elevational view of a modified form of apparatusembodying features of this invention.

The invention described and claimed herein embodies certain improvementsin a felting head employing a gravity system for fiowing fibrouselements of normal size for deposition onto a surface to produce fibrousstructures. The improvement herein provides a simple and efiicient meansfor deposition of the fibrous elements and a more uniform spreading ofboth large and small elements in the manufacture of fibrous structures.As used herein, the term fibrous elements is intended to include anyfree-flowing fibrous elements such as, for example, wooden wafers whichmay range in thickness from 0.001 to 0.125 inch or more and up to 5inches in length or width, with or without tapered ends, such forexample as wafers of the type described in copending applications Ser.No. 78,692, filed on February 28, 1949, now 'Patent No. 2,655,1189; Ser.No. 192,284, filed on October 26, 1950, now abandoned, and Ser. No.344,089, filed on March 23, 1953, or pieces of wooden Veneer, or scrapsthereof, cut into waters or slivers of these dimensions, or choppedstraw or bagasse or fiax shives and the like.

Referring to the drawing, 10 indicates fibrous elements adapted to beintroduced continuously in metered amounts into the inlet chute 11leading into a distributor head 12. It is preferred to make use of anendless belt 13 upon which the fibrous elements 10 are uniformly spreadon the surface thereof as by means described in the copendingapplication 'Ser. No. 200,041, filed on December 9, 1950, now abandoned,for displacement into the inlet chute by a picker 14 rotated in acounterclockwise direction for engagement of the radially extendingblades 15 with the fibrous elements on the surface of the belt '13 fordisplacement into the chute 11. The blades 15 cooperates with thesurface of the belt as it turns about the idler roller '15. Thedistributor head into which the fibrous elements are introducedcomprises a tubular member 16 having an upper end portion 17 incommunication with the underside of the chute =11 and an outlet endportion 18 positioned laterally thereof with a curvilinear main portion19 therebetween through which the fibrous elements are capable of flowgravitationally from the inlet 17 to the outlet opening 18 which facessubstantially vertically in the downward direction. The outlet endportion 18 extends into a circular trough 20 having a radiuscorresponding to the offset of the outlet end portion 1 8 from thecenter of the inlet 1*7 about which the tubing 16 is rotated by means ofa driving motor '21 which supports the tubing at its center upon a driveshaft 22.

The circular trough is formed with upright side walls 23 and 24 and abottom wall 25 which has a plurality of prefer-ably equally spacedopenings '26 each of which leads into a separate down pipe 27 or conduitin communication with the opening and leading downwardly from theunderside of the bottom wall. The lower end of the down pipes are fixedin a manner to permit crosswise adjustment on one or more arms '28 whichextend across the surface upon which the fibrous elements are adapted tobe deposited with the lower end portions of the down pipes being securedto the cross arms in side by side relation to space the outlet endsacross the collecting surface. Attachment to the cross arms may be bymeans of a sleeve 29 or other bracket rigid with the pipes and sl-idablyengaging the cross arms for lateral adjustment and with clamping means,such as a setsc-rew, for securing the sleeve to the arm when in adjustedposition.

In order to arrest the downward flight of the fibrous elements uponissuing from the end of the down pipes 27 and in order to orient andspread the elements for v deposition substantially in parallelism withthe collecting deposited thereon or deposited by adjacent conduits, asplash plate 30 is secured onto the end of each down pipe to extenddownwardly therefrom in angular relation into the path of the elementsissuing from the end of the down pipes to interrupt the flow thereof.The splash plates comprise relatively fiat rigid panels with a swivelconnection 31, such as a ball and socket, connecting the upper end ofeach plate to the lower end of the corresponding down pipe so as toenable angular adjustment of the plate both in a vertical plane and in acrosswise plane to control the deflection of the fibrous elements forinterfelting with one another and to avoid the formation of furrows asthe fibrous elements are deposited to form a layer on the collectingsurface. The collecting surface may constitute an endless screen but itis preferred to deposit the fibrous elements directly onto caul plates32 positioned in end to end relation to provide a continuous surfacemoving constantly in one direction and upon which the fibrous elementsare deposited and with which the layer of fibers are molded to producepanels or boards.

A series of distributor plates 33, preferably formed with verticalcorrugations, are positioned in the space between the splash plates 30and the surface upon which the fibrous elements are deposited further tocooperate with the splash plates in controlling the spreading as well asthe positioning of the elements. For this purpose, the distributorplates are disposed in alignment with the lower end of the splash platesand preferably positioned to incline at an opposite angle therewith tocause reversal of the direction of movement of the fibrous elementsduring travel from the down pipe and the splash plates onto the surfaceupon which the fibrous elements are deposited to form the layer formolding.

In operation, fibrous elements advanced in metered amounts on belt 13are displaced into the delivery chute 11 by the radially extending arms15 of the picker 14 rotating in a counter-clockwise direction. Thefibrous elements thus introduced into the chute 11 travel downwardlythrough the delivery tube 17 which is constantly being rotated by motor21 thereby to parcel out the fibrous elements in uniform amounts aboutthe circular trough 20. The distributed elements pass through theopenings in the bottom wall 25 of the trough into the down pipes 27through which they fall by gravity toward the surface of the collectingwall 32. Since the distributor head parcels out the fibrous elements fordelivery in substantially equal amounts to each of the openings, it willbe apparent that the down pipes, when arranged in side by side relationto the delivery end, will distribute the fibrous elements substantiallyequally across the collecting wall and the splash plates and thedistributor plates cooperating therewith will so control their movementsas to gently lay the fibrous elements fiatwise and in a desiredinterfelting relation onto the surface of the collecting wall.

If furrows form because of non-uniform distribution, the splash plates30 may be adjusted to deflect the fibrous elements in one direction orthe other, or the down pipes may individually be adjusted laterally onthe cross-arm to overcome such non-uniformity. Depending upon the numberof down pipes and the thickness of the layer of fibrous elements to bedeposited, the down pipes may be arranged in one or more rows crosswiseof the collecting wall, such as in two rows illustrated in Figure 1, orin four rows illustrated in Figure 4 of the drawing. When arranged inmore than one row, it is expedient to arrange the splash plates and thedistributor plates to deflect the fibrous elements in the directiontowards each other as regards the direction of movement of thecollecting wall to achieve a desired interfelting relation. Whilelateral distribution across the collecting wall may be achieved byproper adjustment of the down pipes, it has been found that the coverageof the down pipes can be greatly broadened and thereby enable thereduction in the number of down pipes as a result of the use of splashplates and distributor plates in position to arrest the down flight ofthe fibrous elements and to lay the fibrous elements in proper relationon the collecting surface upon delivery.

Instead of securing distribution and delivery of equal amounts offibrous elements in the down pipes by means of a rotating distributorhead which operates in a circular trough, as illustrated in Figures 1and 2, a somewhat similar type of distribution may be obtained with amodification in a distributor head formed of an elongate tubular member40 pivoted at its upper end, as at 41, intermediate the end of chute 11for rocking movement as a pendulum while the upper end of the tubing 40constantly remains in communication to receive fibrous elementsintroduced into the chute 11. The lower end portion 42 of the tubularmember 40 reciprocates throughout its arcuate movement in a similarlyshaped arcuate trough 43 having openings spaced apart longitudinally inthe bottom wall thereof with each opening in communication with aseparate down pipe 27.

Various means may be provided for reciprocation of the tubular member40, depending upon the rate of move ment desired in a particular portionof the trough and variation in movement to achieve more uniformdistribution of fibrous element for feeding into the down pipes. Forexample, as illustrated schematically in Figure 5 of the drawing, thetubular member 40 may be rocked about its pivot 41 in simple harmonicmotion by means of a crank arm 44 pivoted at one end on a pin 45 securedto an intermediate portion of the tubular member while the other end ispivoted on a pin 46 offset from the axis of rotation of a wheel 47rotatably mounted on a stub shaft 48. The wheel is driven by means of anelectrical motor 49 with which it is operatively connected by belts 50and 51 operating between pulleys 52 for speed control. Movement of thetubular member at a more constant speed may be achieved by modificationof the device described wherein the other end of the crank arm 44 ispivoted on a link of the endless member 51 in the form of a chainoperating at constant speed about the sprockets 47 and 52.

As described in the previous modification, the lower end portions of thepipes may be secured in one or more longitudinally spaced rows extendingcrosswise over the collecting surface. The spaced relation between theopenings at the bottom wall of the arcuate trough may be compensated toaccount for the fact that while the rate of delivery of fibrous elementsfrom the tubular member 40 will be constant and uniform, the linearspeed at which the delivery end of the chute moves through the troughmay vary from a higher speed at the center, but in any case to a lowerspeed or dwell at the end whereby a greater number of such elements willbe delivered in the region towards and at the ends of the trough. Byincreasing the number of openings and the number of down pipes towardsand at the ends of the trough and by properly spacing the openingstherebetween in inverse proportion to the rate of travel of the deliveryend of the distributor member over the surface of the trough, the amountof fibers entering each opening for passage through the down pipes maybe kept substantially uniform. In general, the spacing of the down pipesin the trough is arranged to relate to the motion of the outlet 42 andthe spacing at any part is inversely proportional to its relative speedover that part with respect to its speed over other parts of the trough,that is, the spacing is uniform where the speed is uniform and thespacing is approximately that of a sine wave spacing when the tubularmember swings in a simple harmonic motion. As in the previouslydescribed modification, the down pipes are preferably provided at theirends with splash plates positioned to extend longitudinally at a desireddownward tilt across the outlet end and also, if desirable,

' distributor plates which cooperate therewith to lay the fibrouselements gently in position of use upon the collecting surface and whichcan be adjusted to obviate non-uniformities in the rate of delivery andoperation.

It will be evident from the foregoing description that there is provideda new and'improved method and apparatus for the handling of fibrouselements of substantial dimension for deposition thereof to'form auniform layer with the fibrous elements in interfelted relation for usein molding into a strong and well intergrated panel, board or othermolded product. It will be apparent that the apparatus described hereineliminates the possibilities of fibrous elements becoming lodged inrestricted distributor openings so as to interfere with the uniformdistribution thereof in the manufacture of such fibrous structures andthat means are provided for gently and uniformly laying the fibrouselements onto a collecting surface in a desired interfelted relationwith a minimum amount of equipment and in such a manner as to avoid thenecessity for the use of highly skilled labor to effect the operationsthereof.

It will be understood that changes may be made in the details ofconstruction, arrangement and operation without departing from thespirit of the invention, especially as defined in the following claims.

I claim:

1. A method of depositing fibrous elements upon a collecting surface tomanufacture continuous layers with the fibrous elements in uniformdistribution comprising the steps of advancing the said collectingsurface continuously past a plurality of conveyor outlets which arepositioned above and mutually aligned across said collecting surface,moving a distributor outlet uniformly to bring it successively intocommunication with a plurality of conveyor inlets which are at all timesin communication respectively with the said conveyor outlets, andcontinuously feeding fibrous elements at a uniform rate into adistributor inlet which is at all times in communication with the saiddistributor outlet.

2. A method of depositing fibrous elements upon a collecting surface tomanufacture continuous layers with the fibrous elements in uniformdistribution comprising the steps of advancing the said collectingsurface continuously past a plurality of conveyor outlets which arepositioned above and mutually aligned across said collecting surface,moving a distributor outlet to bring it successively into communicationwith a plurality of conveyor inlets which are at all times incommunication respectively with the said conveyor outlets and at a ratein proportion with the space between the conveyor inlets to provide fora uniform interval of time between communications between thedistributor outlet and the conveyor inlets which are at all times incommunication respectively with the said conveyor outlets, andcontinuously feeding fibrous elements at a uniform rate into adistributor inlet which is at all times in communication with the saiddistributor outlet.

3. A method of depositing fibrous elements upon a collecting surface tomanufacture continuous layers with the fibrous elements in uniformdistribution comprising the steps of advancing the said collectingsurface continuously past a plurality of conveyor outlets which arepositioned above and mutually aligned across the collecting surface inat least one row, moving a distributor outlet to bring it successivelyinto communication with a plurality of conveyor inlets which are at alltimes in communication respectively with the said conveyor outlets andat a rate to provide for a uniform time interval in between, andcontinuously feeding fibrous elements at a uniform rate into adistributor inlet which is at all times in communication with thedistributor outlet.

4. A method of depositing fibrous elements upon a collecting surface tomanufacture continuous layers with the fibrous elements in uniformdistribution comprising the steps of advancing the said collectingsurface continuously past a plurality of conveyor outlets which arepositioned above and mutually aligned across the col- 6 lecting surface,moving a distributor outlet uniformly to bring it successively intocommunication with a plurality of conveyor inlets which are at all timesin communication respectively with the said conveyor outlets,continuously feeding fibrous elements at a uniform rate into adistributor inlet which is at all times in communication with the saiddistributor outlet, and interrupting the flow of fibrous elements duringpassage from the distributor outlets to the collecting surface smoothlyto lay the fibrous elements thereon.

5. A method of depositing fibrous elements upon a collecting surface tomanufacture continuous layers with the fibrous elements in uniformdistribution comprisingthe steps of advancing the said collectingsurface continuously past a plurality of conveyor outlets which arepositioned above and mutually aligned across the collecting surface,moving a distributor outlet uniformly to bring it successively intocommunication with a plurality of conveyor inlets which are at all timesin communication respectively with the said conveyor outlets,continuously feeding fibrous elements at a uniform rate into adistributor inlet which is at all times in communication with the saiddistributor outlet, and deflecting the fibrous elements during passagefrom the distributor outlets to the collecting surface to broaden thearea covered by the fibrous elements upon deposition on the saidcollecting surface.

6. Apparatus for depositing and collecting fi brous elements in auniform layer comprising a collecting surface movable uniformly in onedirection, a plurality of separate conveyors having individual inletsand having individual outlets positioned above and mutually alignedacross said collecting surface, a distributor having a single inlet anda single outlet, means for continuously and uniformly moving saiddistributor to bring its outlets successively into communication withthe inlets of said conveyors, and means for continuously and uniformlyfeeding fibrous elements into the inlet of said distributor.

7. Apparatus as claimed in claim 6 which includes means for adjustingthe conveyor outlets in mutual lateral alignment across the collectingsurface.

8. Apparatus for depositing and collecting fibrous elements in a uniformlayer comprising a collecting surface movable uniformly in onedirection, a plurality of separate conveyors having individual inletsand having individual outlets positioned above and mutually alignedacross the collecting surface, a distributor having a single inlet and asingle outlet, means for moving said distributor to bring its outletssuccessively into communication with the inlets of said conveyors, andmeans for continuously and uniformly feeding fibrous elements into theinlet of said distributor, the individual inlets of said conveyors beingspaced one from the other in inverse proportion to the rate of movementof the distributor outlet to provide for substantially equal timeintervals between communication of the distributor outlet with thesuccessive conveyor inlets.

9. Apparatus as claimed in claim 6 in which the conveyor inlets arearranged in a circular path and in which the distributor outlet turns ina corresponding path.

10. Apparatus as claimed in claim 6 which includes a circular troughhaving equally spaced apart openings in the bottom wall thereof each ofwhich is in communication with one of the inlets of the conveyors and inwhich the distributor outlet moves at a constant rate in a circular pathwithin said trough.

11. Apparatus as claimed in claim 8 in which the distributor comprises atubular member and in which the means for moving the distributorcomprises means for actuating the tubular member in pendular movementwhereby the distributor outlet reciprocates through a predetermined arcand in which the conveyor inlets are linearly arranged in an arcuatepath corresponding to that of the distributor outlet.

12. Apparatus for depositing and collecting fi'brous elements in auniform layer comprising a collecting Surface movable uniformly in onedirection, a plurality of separate conveyors having individual inletsand having individual outlets positioned above and mutually alignedacross said collecting surface, a distributor having a single inlet anda single outlet, means for continuously and uniformly moving saiddistributor to bring its outlets successively into communication withthe inlets of said conveyors, means for continuously and uniformlyfeeding fibrous elements into the inlet of said distributor, andinclined plates positioned between the conveyor outlets. and thecollecting surface and in the path of the fibrous elements issuing fromthe outlets to interrupt the flow of the said fibrous elements from theconveyor outlets to the collecting surface.

References Cited in the file of this patent UNITED STATES PATENTS789,135 Baggaley May 9, 1905 987,834 Selden Mar. 23, 1911 1,743,939Thomas Jan. 14, 1930 2,103,769 Drill Dec. 28, 1937 2,243,840 DelivukJune 3, 1941 2,450,511 Harner et a]. Oct. 5, 1948

